c - 输出不符合预期

Question

  // I have used all the header files 
    // code for comparing the directory has matching .recon file  
    // if yes i am printing match found

int main ()
{
    DIR *dp = NULL;
    char *dir = "/home/sv5071184/sample";
    struct dirent *entry;
    struct stat statbuf;    
    char y[20];          
    y[19] = '\0';
    dp = opendir (dir);
    if(dir == NULL)
        return -1;

    while((entry = readdir(dp)) != NULL) {
        lstat(entry->d_name,&statbuf);
        if(S_ISDIR(statbuf.st_mode)) {
            /* Found a directory, but ignore . and .. */
            if(strcmp(".",entry->d_name) == 0 ||
                strcmp("..",entry->d_name) == 0)
                continue;
            strncpy(y,"111111111",9);
            strncpy ((char *)&y[9], ".", 1);
            strncpy ((char *)&y[10], "000", 3);
            strncpy ((char *)&y[13], ".recon", 6);
            if(strcmp(entry->d_name ,y) == 0)
            {
                printf("match found\n");
            }
            else
            {
                printf(" match not found\n");

            }
        }
    }
    printf ( " The value of y is  %s\n", y );
    closedir(dp);
    return 0;
}

我编译执行成功了。但 match not found 在打印 match found 之前打印了五次。请帮忙

Answer 1

这是错误的:

(void) memcpy (y, 0x00, sizeof(y));

这意味着您想要从地址 0 读取顶部复制 sizeof(y) 字节到 y，这当然会出现段错误。

你想要这个:

char y[20] = {0};

或

memset(y, 0x00, sizeof(y));